/*
function document.oncontextmenu()
{
  event.returnValue=false;
}

function window.onhelp() 
{
    return false;
}

function document.onkeydown()
{
    var k = window.event.keyCode;
    if (k == 116) 
    {
        window.event.keyCode    = 0;
        window.event.returnValue= false;
    }
    if (k==122)
    {
        window.event.keyCode    = 0;
        window.event.returnValue= false;
    }
    if (window.event.ctrlKey && k == 82)
        window.event.returnValue= false;
    if (window.event.ctrlKey && k == 78)
        window.event.returnValue= false;
    if (event.shiftKey && k==121)          
        window.event.returnValue= false;
    if (window.event.srcElement.tagName == "A" && window.event.shiftKey)
        window.event.returnValue = false; 
    if (window.event.altKey && k == 115)
    {
        window.showModelessDialog("about:blank","","dialogWidth:1px;dialogheight:1px");
        return false;
    }
    if   (window.event.altKey||k   ==   91) 
          {   
                  //var alertMessage ="禁用ALT组合键";
                  //alert(alertMessage);   
                  window.event.returnValue=false;   
          }   
    
    if (window.event.altKey &&
       (k == 37 || k == 39)) 
    {
        //var alertMessage ="禁用ALT组合键";
        //alert(alertMessage);  
        event.returnValue=false;
    }
}*/